Process for the production of trimethylamineglycol monoborate



' HPatentecl Jan; 13, 1931 KARL tunnel ni oriennL-m-nniiiinm, ERMAN? mtocn'ssron 'rHiaritonUoTIoiv or rmranT YilniainnGLi moii nono aonnirn I is No Drawing. 'Application'filedi March 29, le'zase i i.ubzeeasis;and in'German- 1111 8 1927) a I I I German Patent 7 Specification No." 290,740

describes the production of a beta hydroxy- I ethyl trimethyl ammonium .triborate by allowing atleast 3 molecules of boric acid to act upon 1 molecule vof beta hydroXy-ethyl triinethyl ammonium hydroxide, the structural formula of which latter is 011 year-onion CH:-N

, I V om on I I-Iithertoit has only been possible to prepare the beta hydro yl-ethyl trimethyl ammonium monoborate inaqueous solution, by the addition of a molecule of boric acid'to l molecule of the base. If the aqueous, solution is concentrated, the salt decomposes, and it is impossible to crystallize the saltfrom the viscous syrup. which remains behind.

YIt is possible in 'a surprising manner how- 7 I ever to cause the solidification ofthe syrup, 9 4 I which is formed in concentrating a solution, v i, v I

'Itf reaetsalkaline to jlitmusi and melts at "above 300. ItQdissolVes readily in water andlinfalcohols; "From the hotjconcentrated if the concentration is elfected in a vacuum, for example at about 60 C. or if use is made as initial material of 'a solution which contains morethan 1 molecule, but less than 3 molecules boric acid toflmolecule beta hydroXy-ethyl trimethyl ammonium glycol.

In the latter-process it is even possible to obtain-a practically quantitative-yield of beta I hydroxy-ethyl ,trimethyl ammonium monoborate,uif 2-molecules boric acidlare dissolved toll molecule of the base. Ifa so- I lution prepared with l or more than 1' but less than 3 molecules boric acid isfconcentrated by evaporation according to the'foregoing particulars, a viscous syrup .is left be- I hind,.whieh solidifies in" the-cold forming a .-vitreou's mass, without 'crystallizing. This b syrup is readily soluble in alcohol, but is insolublein ether, acetone, benzene, acetic I ester. Ifthe syrup is'trea ted with-solvents,

in which it is insoluble, as for instance with I acetone, it solidifies after'sometime into crystale of betahydroxy ethyltrimethyl ammonium monoborate. The syrup can also bedissolved first of all in alcohol and then the alco-. I holic solution treated with solvents in which the syrup is insoluble; an oily, syrupy substance is deposited, which solidifies after a little svl ileand alsojconsistsof beta liy droxyethyljtrimethyl ammonium monoborate; it

is also possiblejtouse as initial material an alcoholic solution, ;,of beta hydroxy-ethyl trimethyl ammoniumhydroxide and to treatft'hislwith the necessary amountof boric acid and then .precipitate' the ,monoboratawith V solvents in which it is insoluble lti psurpr s fg-th t f a s ut 'whi h I, o'borate, and not a mixture of monoborate with' liberate;Q f Y Beta hydroxy-ethyl trimethyl ammonium monoborateis a white,niicro-crystalline salt, which crystallizes-With 1 molecule of water; 1

its structural formula is l alcoholic solution it precipitates first in, an oily state: whencoollng, :It'i's insoluble ether,acet1c ester, acetone, benzene and tolui ntei decl-for therapeutic purposes; f

; aam z@ l vfigs, boricacid are dissolved in an aqueous I solution {of 18 gs; beta hydroXy-ethyl "tridrOXyTe't hyl trimeth'yl ammoniui'n I hydroxide ene, lt 'cilnfbe precipitated from the alco holicsolution' by'these'solventsL Thesalt i s;

methyl' ammonium"liydroxideand the solution. fconcentrated;fby evaporation in a II .vacuui'mat about-3094609. The oily residue is dissolved alcohol and the solution, which 'is filtered ifdesired, istreated with acetone. An .oilf ;is again precipitated, and becomes w solid 'after standing 'for'a time." "The solid body is filtered oifla washing'with acetone I carried out and drying in vacuum at I I "The white saltflisibeta hydroXy-ethyl tri m; methyl"ammonium'mon'ob'orate with 1 molew cule water.v I a i 7 p Example [I I An. aqueous-solution of 24 gs; beta hy- I droxide at least one but less than three molecules o'l' boric acid toeach molecule of they hydroxide, concentrating this solution in r ammonium monoborate with 1 v, is treated with 5 gs. boric acid.

ing in dissolving in an alcoholic solution of beta hydroXy-ethyl trimethyl ammonium hydroxide at least one but less than three molecules of boric acid to each molecule of the hydroxide, and precipitating the betahydroxy ethyl trimethylammonium mono-borate'with organic liquids in Whichit is insoluble; V

In testimony Whereoi- I hereunto aliii: my signature;

KARL Lt'iD oKE.

boric acid is dissolved, acetone. is'added to this 1 solution in a quantity such that turbidity no longer occurs upon a further addition. The

deposited precipitate'which is at firstoily soon solidifies; It is filtered ofi, washedwith acetone and ether and dried in a vacuum.

What I claim'isr f 1. A process for the preparation of beta hydroXy-ethyl trimethyl ammonium mono- -borate from beta hydroxy-ethyl trimethyl ammonium hydroxide and'boric acid, consistingin dissolving in anaqueous solution of beta hydroXy-ethyl trimethyl ammonium hydroxide at least one but less than three molecu les of boric acid to eac-h'niolecule of the hydroxide, concentrating this solution in vacuo and precipitating the beta hydroxyethyl trimethyl ammonium mambo-me with organic liquids in which .it is insoluble.

2. A hydroXy-ethyl trimethyl ammonium monoborate from beta hydro y-ethyl trimethyl ammonium hydroxide and boric acid, consisting' in dissolving in an aqueous solution of process for the preparation of beta beta. hydroxyethyl trimethylammonium hy- V vacuo, re-di'ssolving theconcentrate in alcohol and precipitating the beta'hydroXy-ethy'l I rimethyl ammonium monoborate from the solution by organic liquids in Which it is insoluble. o

3. A process for the preparation of beta hydroXy-ethyl trimethyl ammonium monoborate from beta-hydroizy-ethyl trimethyl ammonium hydroxide and boric acid, consisting in dissolving in an aqueous solution of betahydroxy-ethyltrimethylammonium hydroxide at least one but less than three molecules of boricfacid to each molecule of the hydroxide, concentrating this solution; in

vacuo,redisso'lving the concentrate in alcohol and precipitating the beta hydroXy-ethyltrimethyl ammonium monoborate from the solution by acetone. p 4. A process for the preparation of beta hydroXy-et-hyl trimethyl ammonium monoborate from beta hydroXy-ethyl trimethyl ammonium hydroxide and boric acid,'consist- 

